It seems that there are quite a few researchers studying the gap. One of them used a tool to measure that there have been a total of 80 CME based gaps in Bitcoin since December 2017, of which only one, around $21000, has not been filled. The probability of filling the gap is 98.75%, but in reality, there is another gap between $9665 and $9925 that has not been filled. Of course, there was a gap between $84200 and $84790 after he posted, but this does not prevent the probability of filling the gap from exceeding 95%. The most likely gap to be filled in the short term is between $84200 and $84790, unless there is a new gap, which should be the most recent one.